Shear Strength Enhancement and Optimum Dosage Prediction of Fly Ash–Stabilized Cohesive and Cohesionless Soils

Shear Strength Enhancement and Optimum Dosage Prediction of Fly Ash–Stabilized Cohesive and Cohesionless Soils | Research Square window.SnipcartSettings = { analytics: { enabled: false } }; (function() { var accessVector = localStorage.getItem('access_vector') || ''; window.dataLayer = window.dataLayer || []; if (accessVector) { window.dataLayer.push({ user: { profile: { profileInfo: { snid: accessVector } } } }); } })(); (function(w,d,s,l,i){w[l]=w[l]||[];w[l].push({'gtm.start':new Date().getTime(),event:'gtm.js'});var f=d.getElementsByTagName(s)[0],j=d.createElement(s),dl=l!='dataLayer'?'&l='+l:'';j.async=true;j.src='https://www.googletagmanager.com/gtm.js?id='+i+dl;f.parentNode.insertBefore(j,f);})(window,document,'script','dataLayer','GTM-K279D39R'); Browse Preprints In Review Journals COVID-19 Preprints AJE Video Bytes Research Tools Research Promotion AJE Professional Editing AJE Rubriq About Preprint Platform In Review Editorial Policies Our Team Advisory Board Help Center Sign In Submit a Preprint Cite Share Download PDF Research Article Shear Strength Enhancement and Optimum Dosage Prediction of Fly Ash–Stabilized Cohesive and Cohesionless Soils MD. MOIN AKON, Asif Alam Chowdhury, Khan MD Mohaiminul Islam Shovon, and 1 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-8789593/v2 This work is licensed under a CC BY 4.0 License Status: Posted Version 2 posted You are reading this latest preprint version Show more versions Abstract The main objective of this study is to investigate soil stabilization using fly ash, with a particular focus on assessing its influence on the shear strength of both cohesive (clay) and cohesionless (sand) soils.To comprehensively evaluate performance, fly ash (FA) was incorporated into the natural soil at proportions of 8.5\%, 12\%, and 15\%. The effectiveness of these additions was examined through direct shear and unconfined compression tests. Notably, the approach included determining the baseline properties of both sand and clay samples, then systematically introducing fly ash and retesting to identify changes in mechanical behavior. The observed pattern in the results demonstrates a non-linear behaviour with the increase of fly ash content.At 12\% fly ash content, the internal friction angle of sandy soil increased from 29° to 37°, and the cohesion of clayey soil increased from 79.6 kN/m² to 106.4 kN/m², representing improvements of 27\% and 34\%, respectively. Beyond this content, strength declined due to excess fines and reduced particle bonding efficiency. The observed improvements result from different mechanisms: improved particle interlocking and densification in sand, and pozzolanic cementation in clay. A quadratic regression model is proposed to predict the optimum fly ash dosage and corresponding strength gain. In summary, these results confirm that adding 12\% fly ash is highly effective for maximizing mechanical benefit and provides a practical framework for the sustainable stabilization of subgrades, embankments, and other geotechnical applications. soil stabilisation shear strength fly ash industrial by-products regression model Full Text Additional Declarations The authors declare no competing interests. Cite Share Download PDF Status: Posted Version 2 posted You are reading this latest preprint version Show more versions Research Square lets you share your work early, gain feedback from the community, and start making changes to your manuscript prior to peer review in a journal. As a division of Research Square Company, we’re committed to making research communication faster, fairer, and more useful. We do this by developing innovative software and high quality services for the global research community. Our growing team is made up of researchers and industry professionals working together to solve the most critical problems facing scientific publishing. Also discoverable on Platform About Our Team In Review Editorial Policies Advisory Board Help Center Resources Author Services Accessibility API Access RSS feed Manage Cookie Preferences © Research Square 2026 | ISSN 2693-5015 (online) Privacy Policy Terms of Service Do Not Sell My Personal Information {"props":{"pageProps":{"initialData":{"identity":"rs-8789593","acceptedTermsAndConditions":true,"allowDirectSubmit":true,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":586772530,"identity":"0e22d5ad-5466-40cc-8b08-f84991d021e3","order_by":0,"name":"MD. 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The effectiveness of these additions was examined through direct shear and unconfined compression tests. Notably, the approach included determining the baseline properties of both sand and clay samples, then systematically introducing fly ash and retesting to identify changes in mechanical behavior.\u003c/p\u003e\n\u003cp\u003e\u003cbr\u003e\u003c/p\u003e\n\u003cp\u003eThe observed pattern in the results demonstrates a non-linear behaviour with the increase of fly ash content.At 12\\% fly ash content, the internal friction angle of sandy soil increased from 29° to 37°, and the cohesion of clayey soil increased from 79.6 kN/m² to 106.4 kN/m², representing improvements of 27\\% and 34\\%, respectively. Beyond this content, strength declined due to excess fines and reduced particle bonding efficiency. The observed improvements result from different mechanisms: improved particle interlocking and densification in sand, and pozzolanic cementation in clay. A quadratic regression model is proposed to predict the optimum fly ash dosage and corresponding strength gain.\u003c/p\u003e\n\u003cp\u003e\u003cbr\u003e\u003c/p\u003e\n\u003cp\u003eIn summary, these results confirm that adding 12\\% fly ash is highly effective for maximizing mechanical benefit and provides a practical framework for the sustainable stabilization of subgrades, embankments, and other geotechnical applications.\u003c/p\u003e","manuscriptTitle":"Shear Strength Enhancement and Optimum Dosage Prediction of Fly Ash–Stabilized Cohesive and Cohesionless Soils","msid":"","msnumber":"","nonDraftVersions":[{"code":2,"date":"2026-02-26 18:03:15","doi":"10.21203/rs.3.rs-8789593/v2","editorialEvents":[{"type":"communityComments","content":0}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true}},{"code":1,"date":"2026-02-06 07:04:35","doi":"10.21203/rs.3.rs-8789593/v1","editorialEvents":[{"type":"communityComments","content":0}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true}}],"origin":"","ownerIdentity":"5cf28efc-b70c-46d6-819b-8ce3b16a6dee","owner":[],"postedDate":"February 26th, 2026","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"posted","subjectAreas":[],"tags":[],"updatedAt":"2026-02-06T07:04:35+00:00","versionOfRecord":[],"versionCreatedAt":"2026-02-26 18:03:15","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v2","identity":"rs-8789593","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-8789593","identity":"rs-8789593","version":["v2"]},"buildId":"XKTyCvWXoU3ODBz1xrDgd","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}